> Have you tried booting any of the newer daily snapshots ?

no I haven't tried this. 

> >Kernel size exceeds 4
> This may be your problem, a fix went into the bootblocks after 3.0 to
> change how the kernel was mapped.

All I did to fix this booting issue was updating the PROM version to
3.10.13. After a reboot the PROM gave me a hint about the woes. One of
my RAMs was defect. I just pulled the faulty one out and now everything
is working as it should. Anyhow I don't understand why OpenBSD didn't
bother about the faulty RAM...

Thanks for all your input guys. NetBSD rules my universe ;) 

-- 
/sp4rc